AT24C128BMM/TR - 128Kb I2C EEPROM, MSOP-8 | HGSEMI
MPN: AT24C128BMM/TR ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $0.14 | $0.14 |
| 10 | $0.12 | $1.20 |
| 100 | $0.1 | $10.00 |
| 500 | $0.09 | $45.00 |
| 1,000 | $0.08 | $80.00 |
AT24C128BMM/TR Overview
A serial EEPROM (Electrically Erasable Programmable Read-Only Memory) is a non-volatile memory device that communicates over a simple two-wire bus such as I2C. Within the broader memory hierarchy, serial EEPROMs sit alongside flash, EPROM, and FRAM as non-volatile storage, but they are distinguished by byte-level granularity, low pin count, and ultra-low standby current. This makes them ideal for storing configuration parameters, calibration data, and identification records that must persist across power cycles without occupying a parallel memory bus.
Key features include a 64-byte page write buffer, hardware write-protect pin, cascadable addressing for up to eight devices on a single I2C bus, and 1 MHz Fast-Mode Plus compatibility on selected grades. The device supports both Standard-Mode (100 kHz) and Fast-Mode (400 kHz) I2C protocols with low standby current consumption. An integrated Schmitt trigger on SCL/SDA inputs allows reliable operation in electrically noisy environments without external filtering.
From an architectural standpoint, the AT24C128BMM/TR uses a high-reliability CMOS floating-gate cell array with on-chip charge pump generation. The I2C slave interface includes hardware address decoding for three device addresses (A0, A1, A2) plus a fixed 1010 high nibble, allowing up to 8 devices per bus. Internal ECC and write-cycle timers are managed by an embedded state machine that automatically latches data and asserts a Write-In-Progress flag visible via polling.
Typical applications include consumer-electronics configuration storage (TV backlight, audio settings), industrial sensor calibration tables, IoT device identity and security keys, medical instrument parameter storage, and automotive accessory modules. The wide operating voltage range also supports direct connection to lithium battery rails and low-power MCU systems.
When designing with this part, place a 100 nF decoupling capacitor within 5 mm of the VCC pin and add 4.7 kohm pull-up resistors on SDA and SCL. The WP pin should be tied to GND for read/write access or to VCC for full hardware protection. Page-write operations must observe the 5 ms internal write cycle to avoid data corruption.
This page synthesizes distributor pricing, MSOP-8 drop-in alternatives, and practical bus-design notes not found in the standalone manufacturer datasheet.
Drop-in alternatives for AT24C128BMM/TR — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
AT24C128B-MME-T
✅ Drop-In📋 Reference alternative (not in catalog)
AT24C128BN-SH-B
✅ Drop-In📋 Reference alternative (not in catalog)
AT24C128C-MAHM-T
✅ Drop-In📋 Reference alternative (not in catalog)
CAT24C128WI-GT3
✅ Drop-In📋 Reference alternative (not in catalog)
M24256-BRMN6TP
✅ Drop-In📋 Reference alternative (not in catalog)
24LC128-I/MS
✅ Drop-In📋 Reference alternative (not in catalog)
AT24C128BMM/TR Maximum Ratings & Electrical Characteristics
| Memory Type | Serial EEPROM (I2C) |
| Memory Density | 128 Kbit (16,384 x 8) |
| Interface | 2-Wire (I2C), Standard/Fast Mode |
| Supply Voltage (VCC) | 1.8 V to 5.5 V |
| Maximum Clock Frequency | 1 MHz (Fast-Mode Plus) |
| Page Write Buffer | 64 bytes |
| Write Cycle Time | 5 ms (max) |
| Endurance | 1,000,000 erase/write cycles |
| Data Retention | 40 years (min) |
| Standby Current | 1 uA (typ) |
| Operating Temperature | -40C to +85C (industrial) |
| Package | MSOP-8 (MM) |
| Mounting Type | Surface Mount |
| Reel Quantity | 3,000 (TR suffix) |
| RoHS Status | Compliant |
AT24C128BMM/TR Pin Configuration
| Pin 1 | A0 — Device address bit 0 (hardwired) |
| Pin 2 | A1 — Device address bit 1 (hardwired) |
| Pin 3 | A2 — Device address bit 2 (hardwired) |
| Pin 4 | GND — Ground reference |
| Pin 5 | SDA — Serial data (I2C bidirectional) |
| Pin 6 | SCL — Serial clock input |
| Pin 7 | WP — Write protect (active high) |
| Pin 8 | VCC — Power supply 1.8V-5.5V |
Typical Applications
AT24C128BMM/TR is suitable for 6 applications: Consumer TV/Audio Configuration Storage, Industrial Sensor Calibration Tables, IoT Device Identity and Security Keys, Medical Device Parameter Memory, Automotive Accessory Modules, Power Supply Calibration & Trim.
Consumer TV/Audio Configuration Storage
The AT24C128BMM/TR stores channel lists, picture-mode preferences, audio EQ curves, and parental-control PINs in TVs, soundbars, and set-top boxes. Its 128 Kbit density fits typical 16-Kbyte user-preference tables with room for vendor-specific model strings and OUI MAC addresses. I2C integration with the main SoC requires only two GPIO lines, freeing board space versus parallel flash. MSOP-8 footprint simplifies routing in slim 8 mm-thick enclosures. Data retention >40 years exceeds the typical 7-10 year product refresh cycle.
Recommended
Industrial Sensor Calibration Tables
The AT24C128BMM/TR stores per-unit calibration coefficients, linearity curves, and date-code metadata for pressure, flow, and temperature transmitters. Page-write capability allows batching of 64-byte calibration blocks during final test without exceeding the 5 ms write budget per row. Wide -40C to +85C operation supports outdoor and factory-floor deployments. With 1 million write cycles, the part survives decades of field re-calibration cycles in process-industry service.
Recommended
IoT Device Identity and Security Keys
The AT24C128BMM/TR holds X.509 device certificates, symmetric keys, EUI-64 MAC addresses, and secure-boot revision logs in WiFi/BLE/Thread IoT modules. Its 128 Kbit density accommodates a full TLS certificate plus multiple key slots without external secure-element ICs in low-cost designs. WP pin provides hardware tamper-detect by tying to a GPIO that can be forced high on intrusion. 1 uA standby current preserves battery life in always-on storage roles.
Recommended
Medical Device Parameter Memory
The AT24C128BMM/TR stores therapy parameters, dose logs, and patient-device pairing records in portable medical devices such as blood-pressure cuffs, glucose meters, and CPAP accessories. 128 Kbit is sufficient for tens of thousands of measurement records plus device-specific clinical protocols. Wide VCC range (1.8-5.5V) supports both coin-cell and Li-ion-powered instruments. Industrial -40 to +85C rating tolerates disinfection-temperature exposure during routine cleaning.
Recommended
Automotive Accessory Modules
The AT24C128BMM/TR records user preferences, fault codes, and mileage-trip logs in dash-cams, tire-pressure sensors, and aftermarket infotainment modules. Its 128 Kbit density holds dozens of DTC snapshots plus driver-profile settings such as seat-position and mirror-presets. WP pin tied to ignition-controlled rail prevents write access during parked state, protecting against unauthorized configuration changes. Industrial temperature rating is acceptable for cabin-mounted accessory roles.
Recommended
Power Supply Calibration & Trim
The AT24C128BMM/TR stores factory calibration coefficients, OVP/UVP thresholds, and efficiency trim tables in digital-controlled SMPS and battery chargers. Its 128 Kbit density fits per-rail calibration data for multi-output telecom supplies plus logbook records. Fast I2C allows real-time read during soft-start for adaptive voltage scaling. Wide VCC range simplifies integration with 3.3V DSP controllers and 5V legacy housekeeping logic.
Recommended
Recommended Products Summary
Engineering reference data for AT24C128BMM/TR — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | AT24C128B-MME-T | AT24C128BN-SH-B | AT24C128C-MAHM-T | CAT24C128WI-GT3 | M24256-BRMN6TP |
|---|---|---|---|---|---|---|
| Brand | HGSEMI | HGSEMI | Microchip Technology | Microchip Technology | onsemi | STMicroelectronics |
| Package | MSOP-8 (MM) | MSOP-8 (MM) | MSOP-8 (MM) | MSOP-8 (MM) / UDFN-8 variants | MSOP-8 (MM) | MSOP-8 (RM8) |
| Density | 128 Kbit | 128 Kbit | 128 Kbit | 128 Kbit | 128 Kbit | 256 Kbit |
| I2C Max Clock | 400 kHz | 400 kHz | 400 kHz | 1 MHz (Fast-Mode Plus) | 400 kHz | 1 MHz |
| VCC Range | 1.8V-5.5V | 1.8V-5.5V | 1.8V-5.5V | 1.8V-5.5V | 1.8V-5.5V | 1.8V-5.5V |
| Endurance | 1M cycles | 1M cycles | 1M cycles | 1M cycles | 1M cycles | 1M cycles |
| Data Retention | 40 years | 40 years | 40 years | 40 years | 40 years | 40 years |
| Page Write Size | 64 bytes | 64 bytes | 64 bytes | 64 bytes | 64 bytes | 64 bytes |
Key Differentiators
- MSOP-8 footprint compatibility with mainstream 24C128 family (vs AT24C128C-MAHM-T (UDFN-8))
- Lower unit cost at 3000-piece reel (vs Microchip AT24C128BN-SH-B)
- Compact MSOP-8 alternative to higher-density M24256-BRMN6TP (vs M24256-BRMN6TP (256 Kbit))
Design Notes
Decouple the VCC pin with a 100 nF X7R ceramic capacitor placed within 5 mm of the pin and routed with a wide ground-return trace. The AT24C128BMM/TR draws brief surge currents up to 3 mA during page-write cycles; a low-ESR capacitor prevents VCC sag that can corrupt write operations. For battery-powered designs, place a 10 kohm resistor in series with VCC to limit inrush during sleep-mode exit.
Add 4.7 kohm pull-up resistors on both SDA and SCL, sized per the I2C specification for the maximum bus capacitance. Keep the SDA/SCL traces short and parallel, routed over a continuous ground plane to minimize crosstalk. If the EEPROM sits more than 50 mm from the host MCU, insert an I2C buffer such as TCA9517 to avoid signal-integrity issues from cable capacitance.
Always observe the 5 ms write-cycle time after each page write before issuing the next I2C transaction, otherwise the state machine returns NACK and the page is corrupted. Do not leave the WP pin floating - tie it to either GND (write-enabled) or VCC (write-protected). Crossing 7-bit address boundaries without checking will silently write to the wrong device when multiple AT24C128B shares the same bus.
Compliance Information
RoHS and lead-free compliant per HGSEMI product listing (LCSC C42400736). Not AEC-Q100 qualified - for automotive safety-critical roles, choose a Microchip AEC-Q100 EEPROM such as AT24C128C-MAHD-T.
